Abstract: A drill bit assembly is provided for releasably retaining a polycrystalline diamond compact drill bit cutter. Two adjacent cavities formed in a drill bit body house, respectively, the disc-shaped drill bit cutter and a wedge-shaped cutter lock element with a removable fastener. The cutter lock element engages one flat surface of the cutter to retain the cutter in its cavity. The drill bit assembly thus enables the cutter to be locked against axial and/or rotational movement while still providing for easy removal of a worn or damaged cutter. The ability to adjust and replace cutters in the field reduces the effect of wear, helps maintains performance and improves drilling efficiency.

Abstract: A compactible, storable seating apparatus of the type which yields way to accommodate a wheelchair user. The apparatus has a seat bottom and seat back which rotate about a common axis to compact in a vertical position. The seat bottom and back are mounted to a common cantilevered beam which is pivotal about a single stanchion. The seating apparatus can be used in a conventional manner or can be easily pivoted about the stanchion to yield way to a wheelchair user.

Abstract: A row construction for a telescoping seating system includes a rear riser beam having a continuous horizontal slot receiving and encapsulating the rear edge of the footrest panel and a nose beam having a similar slot encapsulating the front edge of the footrest panel. The nose beam is then secured to support members which are mounted to the rear riser such that assembly of these members forces the footrest panel under compression into the opposing slots on the front and rear structural beams. Thus, the footrest panel, the front and rear structural beams and the support members form a horizontal truss. The truss construction is extended to corresponding rows of laterally adjacent sections by extending the footrest panel to bridge the joint between these adjacent sections.

Abstract: In a row seating structure a series of telescoping rows are provided, each row having spaced vertical carriage-mounted columns, each having a cantilever arm adapted to rest upon the next adjacent column when the telescoping structure is extended and a transverse rear riser beam connecting the columns in the row and equipped with forwardly extending supporting arms anchored at their rear upon the riser, and a spectator tread or platform supported by the arms, the arms also providing a seat above the forward end of the tread panel or platform.